Memoir Classics pick the winners. That sounds like an advert, but it was true of their recent McCormack disc (5/93) and it holds good now with their Gigli. There is a well-judged balance of song and opera, solo and duet, early and middle-period recording. The honeyed lyric-tenor (almost countertenor here) is heard in ''Je crois entendre encore'' from Les pecheurs de perles, the lyricdramatic in Andrea Chenier's Improvviso. Gigli the charmer, and indeed the humorist, is there in ''La donna e mobile'' and ''Che gelida manina'' (the only Rodolfo who realizes he has cracked a joke at ''vivo''). Then there are excellent examples of those lovely cheap songs written by De Curtis, Bixio and other masters, all absolutely right in choice and performance.Not everything is right: the Mefistofele ''Dai campi, dai prati'' and the Forza del destino duet, ''Solenne in quest'ora'' play a semitone high, and Di Chiara's La spagnola is conducted not by Walter Goehr but Lawrance Collingwood. Also there are some curious anomalies in the transfers: not much sign of the 78rpm originals, for instance, till it comes to ''Solenne in quest'ora'' and then again in Toselli's Serenata where the surfaces, vigorous and pocky, proclaim authenticity. But how well the Cavalleria duet, ''Tu qui, Santuzza'' sounds. And how Dusolina Giannini gives him a run for his money here. A superb performance.'